Which element is not produced by stars?

Which element is not produced by stars?

• A. Hydrogen
• B. Helium
• C. Carbon
• D. Oxygen

Answer: (A)

Stars synthesize heavier elements by nuclear fusion, starting with the hydrogen that fills most of the universe. The light elements hydrogen and helium were made in the Big Bang, not inside stars. Inside stars, hydrogen nuclei fuse to form helium, and as stars evolve, helium can fuse further to make carbon and oxygen (and many other elements in later stages). Because of that, hydrogen is not produced by stars; it’s the fuel they use. The elements listed—helium, carbon, and oxygen—are all produced inside stars through these fusion processes.

Stars synthesize heavier elements by nuclear fusion, starting with the hydrogen that fills most of the universe. The light elements hydrogen and helium were made in the Big Bang, not inside stars. Inside stars, hydrogen nuclei fuse to form helium, and as stars evolve, helium can fuse further to make carbon and oxygen (and many other elements in later stages). Because of that, hydrogen is not produced by stars; it’s the fuel they use. The elements listed—helium, carbon, and oxygen—are all produced inside stars through these fusion processes.